1. Field of the Invention
The present invention relates to a projectile having a rotating band secured to the projectile body. The exterior surface of the rotating band engages the rifling of a gun barrel during firing thereby imparting spin to the projectile.
2. Discussion of the Prior Art
In spin stabilized projectiles, the spin is transferred to the projectiles by one or sometimes several rotating bands arranged one behind the other.
U.S. Pat. No. 3,910,194 shows that it is known to provide circumferential grooves in the rotating band to receive the rearwardly sheared off rotating band material. Customarily, the width of such grooves is no greater than 4 mm. The rotating bands may be composed of copper, soft iron or plastic.
In these known rotating bands, radial contact between gun barrel and rotating band takes place only by way of the band ribs between the grooves. This contact produces a radial pressure on the projectile 1 called the rotating band pressure.
Particularly if thin projectile bodies are employed in which the ratio of the wall thickness of the projectile body to the caliber of the gun barrel is customarily .ltoreq.0.05, the projectile reacts with particular sensitivity to radial pressures since certain points dependent on the geometry of the projectile may be subjected to great material stresses. As a result of these stresses the projectile body may be pressed inwardly so that the seal against the propelling gases usually provided by the rotating band is no longer ensured.